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题目材料：
Insect predators usually keep the number of aphids in crop fields low. However, sometimes the aphid population explodes in size, causing major damage. Much explosions happen when unusually cold weather keeps the number of aphids low in the spring. One possible explanation is that, with fewer aphids to feed on, the predator population also drop, and in summer when the aphid population starts to grow there are not enough predators to keep it in check.
Which of the following, if true, would most strengthen the explanations given for aphid population explosions?
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A.When a pesticide that affects both aphids and predators is applied to a field, once the pesticide washes away there is an aphid population explosion
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B.Insect predators of aphids can survive for long periods without food as long as the weather remains cold
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C.When weather is unusually cold in the spring certain crops grow more abundantly in the following summer increasing the food supply for aphids.
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D.The predators of aphids can die from causes other than starvation such as disease and severe weather.
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E.Aphids can reproduce very quickly if they have sufficient food.
E显示答案
